# Using differential variability to increase the power of the homogeneity test in a two-sample problem

@article{Liu2018UsingDV, title={Using differential variability to increase the power of the homogeneity test in a two-sample problem}, author={Guanfu Liu and Yuejiao Fu and Pengfei Li and Xiaolong Pu}, journal={Statistica Sinica}, year={2018} }

We consider a particular two-sample homogeneity testing problem often encountered in case-control studies with contaminated controls, or in detecting a treatment effect when some subjects are not affected by the treatment in biological experiments. We propose an EM-test designed to simultaneously detect mean difference and differential variability in the two samples. We show that the EM-test statistic has a chi-squared null limiting distribution. The asymptotic properties of the EM-test under…

## 4 Citations

EM-test for homogeneity in a two-sample problem with a mixture structure

- MathematicsJournal of applied statistics
- 2020

ABSTRACT In many applications such as case-control studies with contaminated controls, or the test of a treatment effect in the presence of nonresponders in biological experiments or clinical trials,…

Logarithmic minimum test for independence in three-way contingency table of small sizes

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ABSTRACT The main aim of this paper is to propose a logarithmic minimum test for the three-way contingency table. The second aim is to compare the quality of independence tests by using their power.…

Semi-parametric homogeneity test and sample size calculation for a two-sample problem under an inequality constraint

- Mathematics
- 2021

Some contributions to practice of 2 × 2 contingency tables

- MathematicsJournal of Applied Statistics
- 2018

ABSTRACT This paper focuses on contingency tables (CTs) used to accept or reject hypothesis that two categorical features are independent. This paper promotes a new view of the essence of CTs.…

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